Writing for The Daily Mail, Lord Ashcroft and the co-author of his book, Isabel Oakeshott, profess:

A distinguished Oxford contemporary claims Cameron once took part in an outrageous initiation ceremony at a Piers Gaveston event, involving a dead pig. His extraordinary suggestion is that the future PM inserted a private part of his anatomy into the animal’s mouth.

The source — himself an MP — first made the allegation out of the blue at a business dinner in June 2014. Lowering his voice, he claimed to have seen photographic evidence of this disgusting ritual.

Ashcroft says the claim was later repeated by the same MP, and then mentioned a third time, where he disclosed further details including the size of the photo showing the alleged “porking” and the name of the person who may possess it.

“The pig’s head, he claimed, had been resting on the lap of a Piers Gaveston society member while Cameron performed the act,” Ashcroft writes.